Example III page 8: 1. 5.17 g of fertilizer was added to a 250.0 mL volumetric flask and water was added to make it up to the mark. 2. 20.00 mL of this solution was pipetted into a conical flask. 3. A slight excess of precipitating agent was added to precipitate the phosphate ions as MgNH4PO4. 4. The precipitate was filtered, washed with water and then converted by heating into Mg2P207 5. The mass of Mg2P207 was 0.0312 g Calculate the percentage by mass of phosphate in the fertilizer. Ans%(PO4³) = 6.42% Solution: mass of fertilizer = 5.17 g mass of Mg2P2O7 = 0.0312 g Total volume = 250.0 mL Used Volume = 20.00 mL 2 PO43- Mg2P207 0.0312 g

Example III page 8: 1. 5.17 g of fertilizer was added to a 250.0 mL volumetric flask and water was added to make it up to the mark. 2. 20.00 mL of this solution was pipetted into a conical flask. 3. A slight excess of precipitating agent was added to precipitate the phosphate ions as MgNH4PO4. 4. The precipitate was filtered, washed with water and then converted by heating into Mg2P207 5. The mass of Mg2P207 was 0.0312 g Calculate the percentage by mass of phosphate in the fertilizer. Ans%(PO4³) = 6.42% Solution: mass of fertilizer = 5.17 g mass of Mg2P2O7 = 0.0312 g Total volume = 250.0 mL Used Volume = 20.00 mL 2 PO43- Mg2P207 0.0312 g

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter19: Transition Metals And Coordination Chemistry

Section: Chapter Questions

Problem 14E: A 2.5624-g sample of a pure solid alkali metal chloride is dissolved in water and treated with...

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